I originally purchased this amp so I could run it at approximately the same wattage (1100) stereo as I was running my Carvin DCM1000 bridged mono (1000 watts). Today, I finally AB'd both amps run in stereo mode. I fully expected the QSC to be louder than the Carvin (550 watts into 8 ohms), but the Carvin is definitely louder in stereo even though it's rated at only about 200 watts at 8 ohms. What gives? Is it the input sensitivity issue again? Another problem: The amp has some bad rattles inside when it's setting on top of my cabinet. Is this normal for these amps? My Carvin is dead quiet; the fan is quieter too. Well, is this amp really worth about 3 times as much as my Carvin? Should I sell this thing right away and keep the Carvin?